The subject application relates to electronic registration systems and methods. While the systems and methods described herein relate to bow and skew correction using electronic registration in digital images and the like, it will be appreciated that the described techniques may find application in other image correction systems, other xerographic applications, and/or other image correction methods.
Conventional electronic registration techniques require high resolution scan line buffers to span the range of raster line bow and skew that is being compensated. Some methods reduce the memory requirement for resolutions of interest, but do not compensate the halftone screen for bow and skew, thereby incurring a high risk for color-to-color moiré.
Electronic registration is used to save cost over currently practiced opto-mechanical methods. One consideration in conventional electronic registration applications is the cost of the scan line buffers needed to span a skewed and bowed scan line, as it is desirable to bring down the cost of the scan line buffers.
One such conventional electronic registration method performs electronic registration after halftoning is performed, and requires high resolution (2400 spi) scan line buffers to span the range of raster line bow and skew being compensated. Conventional systems require a plurality of image pixel data raster lines that span a raster output scanner (ROS) physical raster line, all of which need to be held in memory to extract the pixels of interest. For conventional 2400 spi pixels and rasters, approximately 100 high speed binary scan line memory buffers are needed per millimeter of compensation.
If raster buffering is performed in the low resolution contone state, the memory requirement for the image data can be reduced by approximately one half for the current resolutions of concern (e.g., 2400 spi 1-bit/pixel requires twice the memory of 600 spi 8-bits/pixel). However, existing electronic registration methods that attempt to reduce memory requirements fail to compensate the halftone screen angle for bow and skew.
Accordingly, there is an unmet need for systems and/or methods that facilitate reducing the cost of expensive scan line buffering for electronic registration for low cost products while mitigating color-to-color moiré, and the like, while overcoming the aforementioned deficiencies.